1. Technical Field of the Invention
The present invention relates generally to an electric power steering device equipped with a steering assist motor to assist with steering of a steering wheel.
2. Background Art
Japanese Patent First Publication No. 2003-267248 discloses an electric power steering device which works to measure a steering torque of a steering shaft of an automotive vehicle and control an electric motor (i.e., a steering assist motor) as a function of the measured steering torque to produce a steering assist torque to the steering shaft.
Electric power steering devices of the type, as taught in the above publication, have the disadvantage that when the driver puts the vehicle into the garage at low speeds, making small turns, it takes a lot of time and effort on the part of the driver, resulting in the fatigue of the driver. Particularly, when the driver backs the vehicle into the garage, the driver needs to operate the steering wheel while securing the safety behind the vehicle. The driver may, thus, overturn or over-return the steering wheel, experiencing a difficulty in moving the vehicle into the garage correctly.
Recently, automotive vehicles which are equipped with a rear monitor camera or capable of being backed into the garage automatically using such rear monitor camera or rear sensor have been used, but however, resulting in increased costs of the vehicles.